2(x-y)/3-(x+y)/4=-1化简得8(x-y)-3(x+y)=-12 ①
6(x+y)-4(2x-y)=16化简得3(x+y)-2(2x-y)=8 ②
由②得
3(x+y)=2(2x-y)+8 ③
将③整体代入①得
8(x-y)-2(2x-y)-8 =-12
8x-8y-4x+2y=-4
4x-6y=-4
2x-3y=-2 ④
由②去括号得
3x+3y-4x+2y=8
即-x+5y=8 ⑤
⑤*2+④得
10y-3y=16-2
7y=14
y=2
代入⑤得
-x+10=8
x=2 2(x-y)/3-(x+y)/4=-1化简得8(x-y)-3(x+y)=-12 ①
6(x+y)-4(2x-y)=16化简得3(x+y)-2(2x-y)=8 ②
由②得
3(x+y)=2(2x-y)+8 ③
将③整体代入①得
8(x-y)-2(2x-y)-8 =-12
8x-8y-4x+2y=-4
4x-6y=-4
2x-3y=-2 ④
由②去括号得
3x+3y-4x+2y=8
即-x+5y=8 ⑤
⑤*2+④得
10y-3y=16-2
7y=14
y=2
代入⑤得
-x+10=8
x=2